Copyright Malcolm Faed.
Images and text may only be copied with the permission of the author.
This blog includes personal things of interest including electric vehicle conversion. I have documented the conversion of a petrol (gas) powered vehicle to Electric. http://www.austinev.org/evalbum/1149.
The blog now documents the conversion of a BMW E30 to electric.

Monday, 23 March 2009

I tried variable switching frequency(Parameter 412)this morning but it works the opposite to what I was hoping. It does sound cool though!

It increases frequency with RPM as per the manual. I wanted a low frequency at low RPM.

Low switching frequency(Parameter 411)seems to be the keyto prevent lurching and brief rear wheel lock up when decelerating to a stop. Icould also try raising the stop frequency(Parameter 123)but I didn’t like this set higher than 0.

Friday, 20 March 2009

I began this planing this project after visiting the AEVA field day in October 2007. After much planing and calculating in Excel, I started purchasing parts (the motor) in December 2007.

It took a while to find a vehicle that would suit. I looked at Toyota Town Aces, Suzuki Carrys Toyota SBVs and finally settled on a Toyota Hilux extra cab ute in April 2008. My requirements were to carry 360kg of SLA batteries + inverter and have 4 seats (for kids) without significant chassis modification.

It was cheap for the model, but reasonably tidy. Some rust that needed dealing to but OK. This model is popular with young guys and this one had been painted black and had dark tinting, so I had to de-bogan it as well.

To get to the point, I finally got it registered on the 7th of March.

I am very happy with its performance on road. Thanks to Tuarn (acmotor on the AEVA formus) for your inspiration in leading the way, despite me bing first to register.

The tweaking and fiddling with settings took a while but got there in the end. It even has regeneration which is necessary in my hilly area.

If there are any other registered industrial AC conversions around, do challenge my "subject" as I would be interested to know more about theirs, and concede to a lesser accolade of Australia or NSW.

During operation the motor was cool enough but as soon as there was no air movement, the heat had nowhere to go.

I removed the shaft fan and replaced it with a 10 inch 'ICE' brand electric fan.

The fan was attached to an aluminum plate to prevent air escaping around the fan. Coincidentally the fan mounting holes almost line up with the 4 bolt holes. I 'moved' the holes in the plastic fan by about 5mm and it looks like it was made to fit!

There is a 50 deg C 'clickson' NO thermal switch that drives a relay, that in turn drives the fan direct from the battery. This way the fan can run if necessary even if the key is off when most needed.

Air flow around the motor is very will designed. The air is blown toward the rear of the motor length ways down the cooling fins and the air exits at the rear of the motor.

i have also removed the air dam from the radiator opening to allow improved cooling.

Start voltage was 657v. 100%SoC according to the greensaver battery data sheet.

End voltage was 621v. 50%SoC.

Energy used (probably) = 6kwh. Efficiency = 250Wh/km

I am mixing measurements here however, the kwh counter read 8.2kwh. This is motor energy both driven and regen. This gives 2.2kWh regen which I find very hard to believe, considering the charge efficiency will not be great.

For now I will rely on the pack voltage for SoC while stationary. I have printed out a lookup table to translate voltage into SoC.

I had the regen set for 10kW (66.6%). This gave over voltage warnings (801+ volts) and was a bit much for the batteries at 16v per cell, but did not trip on a full charge. This equates to a charge current of 12.5A. minus about .5A through the balance circuit.

I have backed this off to 8kW (53.3%) to try and minimise over voltage on the batteries.